I bought a Wilwood master cylinder (for the Toyota 4x4 brake upgrade) but can't find a thread to match the output ports. According to Wilwood the thread is a 1/8-27 but it's not. I even went to the hardware store to double-check with their brass fittings. It's also not the M10 thread on the stock brake lines. An AN3 has the same thread pitch but it's loose and doesn't have the inverted flare tip to seal. I've seen adapters for an M10 fitting but I'm running AN3 hoses from the MC to the distribution block, so that won't work for me. Does anyone know what it really is? Thanks.